Liquid-level indicator



Jan. 18, 1927.

\l. P, CLEAR LIQUIDLsvL INDICATOR Filed July 2. 1924 Mc ron A1D. CLEA nNVENTOR TTOR/VE Y M M f. M W w Patented Jan. 18, 1927.

unir-rre Aras PATENT FFIGE.

LI'QUIDFIEVEL INDICATOR.

,and pressure variations.

In my indicator I empfloyl a klfloat in Vthe `tank and connect this'float fvith'a -llexible air tight chamber. The space inside of-th-ischamber is connected by means of suitable pipes with an indicatoradapted to register variations in the pressure in these pipes. 1 arrangethe connections between the float and the chamber so that the changes inthe pressure in this chamber are proportional to the changes in theheight of the liquid in the tank. Therefore by properly calibrating thescale of my instrument I can use it toindicate the amount of liquid inthe tank.

My invention is more fully described in the accompanying specificationand drawings in which- I Fig. 1 is an elevation partly in section of myindicator, showing also a tank and the tank fixture, Fig. 2 is a sideview of the tank fixture, and Fig. 3 is a sectional view of theindicator, the section being taken on the line 1-1 (Fig. 1).

My indicator consists of a block 1 which may be of metal or some othersuitable material (Figs. 1 and 3). On one side the block has alongitudinal cylindrical aperture 2 closed at the bottom with a plug 3.At the other side there is a recess 4 into which a glass tube 5 isfitted, being clamped between elastic Washers 6 by means of a nut 7 witha central aperture 8. The lower portions of the glass tube 5 and of thecylindrical chamber 2 are connected by means of a passage 9 therebyforming a U-tube. An indicating liquid 10 is placed in this U-tube. Ascale 11 is placed in the recess 4, partly surrounding the glass tube 5.i

The legs 2 and 5 of this U-tube are provided with packing bushings 12 ontop for connect-ing pipes 13 and 14, the bushings being clamped aroundthe pipe ends by means of gland nuts 15 thereby eecting air tightconnections for the pipes 13 and 14.

These pipes extend to a tank 16 with a liquid 17, A tank fixture 18 isattached to lthe 'top 4 of the tank 'by means yof fa clamping nut19fittingfover'a base20. 'fIliis'fixbure is provided with pack-ingglands211an`d 22 .for the endsof thefpipes 313 and V14. Passages 23 and 24connect these'pipes with airtlig'ht chambers`23 separated 4by a Walll 24:amd `cl osed on'the'oppositesides, with )flexible diaphragms 25 and 26.The centersof these diaphragms are provided with .reenforced portions 27vto which are attached the ends of the'voperating rods 28'1and 29. Theserods or levers are=hingedtogether at t'he vpoint 30' and are drawntogetherby means of a spring IThe :hinge or pivot -80 isfat tached tothe lower extension 32 offthe .fixture 18.

A cam 33 is fastened to a small shaft 34 between the legs 32 of thefixture 18. The ends of theshaft 34 are rigidly attached to links 35connected to a cork float 36 by means of pins 37.

The operation of this device is as follows. For each position of thefloat 36 the cam 33 takes a corresponding position, operating thediaphragms through rods 28 and 29 in such way as to move one diaphragmin and the other out of their respective chambers, thereby changingtheir air contents and displacing the indicating liquid in 'theindicator. For instance, if the amount of liquid in the tank isincreased, then the float 36 rises, the cam 33 pushes the arm 29,thereby expanding the chamber 23" and drawing the air from the leg 5 ofthe U-tube. The other arm 28, at the same time, will be drawn in by theaction of spring 31, thereby pushing the diaphragm 25 and forcing theair from the chamber 23 into the le 2 of the indicator U-tube. Theindicating iniquid, accordingly, will be displaced from the leg 2 intothe leg 5. The amount of such displacement depends only on the shape ofthe cam 33 and on the dimensional proportions between the arms 28 and 29and links 35. The indicating liquid forms a movable separator betweenthe air volumes in the pipes 13 and 14, and it is evident that the forniof this indicator may be changed considerably without deviating from themain principle of my invention.

With two pipes and two chambers, the instrument is not affected bytemperature chan es, as any change in pressure in one cham er and pipeis accompanied by the correspondin change in the other piY e. NOW if the8.11' volumes on both sides of t e lil) U-tube are equal, then thesechanges in pressures will be fully compensated in their effeet on theposition of the indicating liquid in the U-tube.

The lixture 18 may be provided with a flange 47 which is attached to aring i9 on top of tank with screws 50.

The U-tube may contain liquid l0 up to certain mark on the scale, sothat for installation it is necessary to place the corresponding amountof vliquid in tank before the pipes 13 and 14: are connected. rlCheindicator may be made, however, to containliquid up toV Zero point onthe scale by providing sutlicient space for this liquid below zeropoint. In that case the installation may be made with an empty tank.

Important advantages of my indicator are that it can be used for anysizes and capacities of tanks, that it is not aiiected by teniperatureand pressure variations, can indicate at any point away from the tank,and can be used for liquids with dilerent specific gravities. Y

I claim as my invention:

In a liquid level indicator, the combination with an indicating devicecomprising two chambers, means to indicate dii'ference ot' air pressurebetween said chambers, a tank, a lixture member in said tank, means toattach said member to the top cover of `said tank, lsaid member 'beingprovided with depressions on its opposite sides, corrugated flexibleplates covering said depressions, said depressions with said platesforming closed chambers,said member being provided with separate tubularapertures extending from its top to said second mentioned chambers, apipe extending from one ot said chambers to one chamber ot saidindicating` device, a second pipe extending from the other aperture tothe second chamber of said indicat ingi device, rods attached to thecenters of said flexible plates, means to draw said rods together, a cambetween said rods, means to reta-tively support said cam, a rod attachedto said cam, and a float on the end of said rod.

VICTOR P. CLEAR.

